Cell Breathing..

[patek1968]

Hi, just wanna asked about this thing,during daytime cell's rscp was ok, but during night and peak hours,rscp degrades..does this affects rscp degradation due to cell breathing?

[scorpion]

Yes for 3g, may be that particular site having lots of 3G handsets in the vicinity and heavy data usage...

[patek1968]

so you mean that more users affects rscp?

[Mctest]

Yes for 3g, may be that particular site having lots of 3G handsets in the vicinity and heavy data usage...

May be Ec/No?What do you think?

[patek1968]

actually i think the same for ec/io..but i wanted to justify this if cell breathing affects rscp and how?thanks..

[Processor]

For the records.....

Cell breathing is the increase or decrease in a cells coverage area due to the number of users or load on it....so please ask ur question clearly:D

[s.sunilpal123]

No...I think RSCP should not be affected since it does not depend on system loading. Pilot channel is a broadcast so it won't matter how many users are using data. The pilot keeps transmitting at the same power so cell breathing is out of question....

Other views are welcome...And patek1968...pls add rep if this helps....:)

[mobilek530]

Cell breathing is applicable for 3G and CDMA2000 both as power is shared

[rishi]

Yes it definetly affects RSCP for a site during cell breathing.

[srilasitha]

RSCP power adjustment is the method used in cell breathing. But this has to be configured in the RNC.

this would allow other retaining users to enjoy the network with same Ec/Io.

Cell breathing does not reduce Ec/Io.

[patek1968]

Well, I can think of load balancing when it comes to cell breathing.that there is a required minimum load threshold that a cell can transmit..therefore, it reduces its intended coverage and rejects all those new users and handover them to neighbors to avoid further more degradation..its my opinion..

[s.sunilpal123]

Due to system load increase, I0 will increase. Ec is constant the pilot being transmitted at constant power at all times. So the effective cell coverage radius will decrease due to loading... The minimum required receiver sensitivity too will increase as UL noise rise increases due to loading.

[patek1968]

Yes but I just want to know if this phenom affects RSCP and elaborate how..if someone knows please enlightened me..thanks..

[Md.Moniruzzaman]

Actually cell breathing doesn't have any impact on RSCP. It rises noise level Io. So it hamper service coverage. Suppose for a particular service if CPICH_ RSCP=-80dBm sufficient,then at loaded/cell breathing stage CPICH_RSCP=-70dBm may need for accessing the mentioned service.In this way effective service coverage affect.

[patek1968]

thanks mate.I now understands..

[cococrunch]

This is how I understand it. Cell breathing
doesn't affect RSCP,
affects Noise but not Energy/chip(Ec) so thats why we have poor Ec/No during high load.

Suppose UE is situated in RSCP -80dBm, still very good coverage but due to high load Ec/No is bad, like -15 dB.
UE tx power at this moment is reaching limit 21 or 24 dBm to reach BTS to compensate poor signal quality(Ec/No).

That is why coverage(UL) is shrinking when in high load even though you get -80 dBm RSCP.

[cococrunch]

I have put a comment which makes me think twice so I edited.

[jan74]

Absolutely 100% certain that RSCP is not affected by breathing. They are unrelated as Ec is fixed.

However, EcNo is not fixed as No changes. Therefore, your EcNo deteriorates which effectively means the cell size has reduced.

There is a possibility though that your cell size changes slightly at night due to changes in how the Rf signal fades. But this should be relatively slight.

[Mdaf]

Besides the below , it's also important to consider the UL,as more traffic increase the UL load increases and the UEs now should increase their power to overcome this load increase. Which is the same as limiting UL coverage

[erastus]

Cell breathing only affects Ec/No. It has nothing to do with RSCP. Maybe the antenna could be been over downtilted

[tukangoptim]

this picture

28204

:)

[lihanbok]

this picture

28204

:)
Your image is very good, Could you please share full documents? Thank you so much.
Regards,
Lihanbok

[tukangoptim]

Lihanbok,
that pic is simple LDB process, not cell breathing, which probably the reason of coverage "shrinking" in high load situation.
especially if u set parameter to easily trigger , and high pace of pilot adjustment.

its from huawi hedx am pretty sure u can find it in this great forum.. :)

[melkaiy]

cell breathing affects the the rscp received by the ue. load admission and load control involves power adjustments you can check the LC and AC parameters.

if this one helps please add reps :)

[melkaiy]

you can also check the sho overhead, you can also check the sudden drop in radio access as you go along with the drive test. notice the rscp drop which makes the coverage smaller compared with normal occasions. cell breathing is accompanied by call drops/fails which indicates over load in capacity. and if you already figured out that the number of radio access bearer has been reduced you can now recommend to increase the offset in load margin if you operator allows parameter change.

if this one helps please add reps :)

[scorpion]

How to determine that the call drops are due to RSCP /Ec issue ?
By the way Cell Breathing is related to Ec or RSCP ?

[lamagica]

in my opinion, it is mainly related to Ec N0, more users attach to the same cell / sites will raise the noise floor for that particular cell / sites. hence, EcN0 would be lower.